CVE-2021-43825

Use-after-free in Envoy

Description

Envoy is an open source edge and service proxy, designed for cloud-native applications. Sending a locally generated response must stop further processing of request or response data. Envoy tracks the amount of buffered request and response data and aborts the request if the amount of buffered data is over the limit by sending 413 or 500 responses. However when the buffer overflows while response is processed by the filter chain the operation may not be aborted correctly and result in accessing a freed memory block. If this happens Envoy will crash resulting in a denial of service.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.09%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: envoyproxy envoy
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-43825?
CVE-2021-43825 has been scored as a medium severity vulnerability.
How to fix CVE-2021-43825?
To fix CVE-2021-43825, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43825 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43825 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43825?
CVE-2021-43825 affects envoyproxy envoy.
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